The aims of this project are to definitively determine the long-term risks associated with kidney donation and the short- and long-term risk of liver donation. These represent 2 separate situations: a) living kidney donation has been done for the last 4 decades and the short-term risks have been well-defined. But (previous retrospective) long-term studies have suffered from inability to contact all the donors. In some of these studies, it has been shown that some donors have hypertension, proteinuria, and renal dysfunction. And it is know that some donors have developed ESRD. Yet, because follow-up is incomplete, it is unclear whether the risk to the donor exceeds that of the general population. We plan a long-term study, in which we maintain regular contact with the kidney donors, to determine: the risk of developing hypertension, albuminuria, and renal dysfunction (and any progression should they develop). We will also determine the incidence of type 2 diabetes and study whether nephropathy occurs more rapidly in the uninephrectomized donor. And we will study the impact of postdonation proteinuria on cardiovascular risk. Living donor (especially right lobe) liver transplantation is a relatively new innovation. There are few short-term and no long-term follow-up studies. We plan a long-term study, in which we maintain regular contact with the donors to determine both short- and long-term term consequences of living donor liver transplantation. Both of these follow-up studies are necessary to be able to provide accurate information to prospective donors.